Then there's ex-GoT star Pedro Pascal, who faced Ser Gregor in a brutal bout as Oberyn Martell. Born April 2, 1975, he's now 41 – which makes him 13 years and 7 months older than his one-time opponent.

And how about the other Mountains? Björnsson is actually the third actor to play Ser Gregor – and he's by far the youngest.